Most geotechs are familiar with the Journal of Geotechnical and Geoenvironmental Engineering (JGGE), one of the (if not the) premier journal in the industry. It’s published by the ASCE’s Geo-Institute (G-I) and accounts for about 20% of the revenue of the G-I organization.
The G-I’s President, Dr. Jean-Louis Briaud, convened a task force in early 2009 to investigate if the JGGE is “adequately serving as a venue for practice oriented papers.” According to the final report from the Proposed "Journal of Geotechnical Engineering Practice" Task Force, the reason for the task force is that:
The only portions of the World Trade Center towers that survived the attack on 9/11 were the basement slurry walls, part of the original shoring and foundation system. The National September 11 Memorial and Museum at the World Trade Center that is currently under construction will preserve a portion of that wall making it the largest exhibit the museum will offer. The wall section displayed will be 62-ft by 64-ft.
The existing slurry walls are being incorporated into the foundation system of the new facility but not without some improvements. The are adding some kind of foundations improvements to stabilize the toe of the walls, the New York Times article calls them caissons, but I don’t know if its a tangent or secant wall or something else. They are also lining them with additional concrete and reinforcement in front of the walls along with additional tiebacks to stabilize them. In the portion of the wall that will be displayed, a counterfort wall will be constructed behind it and new tiebacks will be installed on the front. Work for the counterfort wall will be done by hand in order to avoid the existing tieback cables. All of the existing tiebacks will be left intact. Check out the NY Times article for a great graphic showing the system. (Illustration by New York Times)
[Editor] For crying out loud. Two weeks later, and I finally notice the title of my post was 20 years off! Its the 40th anniversary, not the 20th. Sheesh! [/Editor] It’s hard to believe that such a tremendously historic scientific and cultural event is celebrating its 20th Anniversary this month! On July 20, 1969, Apollo 11 astronauts “Buzz” Aldrin and Neil Armstrong became the first humans to set foot on the Moon. [Astronaut Edwin E. Aldrin near a leg of the Lunar Module. (From enwiki), NASA Source]
One of the first featured articles I published on GeoPrac was a remarkable narrative by my NCS Consultants, LLC colleague, Dr. Ed Nowatzki, sharing his recollections of his work on the geotechnical (soils engineering)aspects of the design of the first lunar lander or LM. I was doubly reminded of his article recently, first because of the milestone anniversary, but also because a different spacecraft was having some soil-related trouble on the Planet Mars.